thE poliCE mEt DiFFiCultiEs At thE BEginning oF thE CAsE thAt ______.
A．thEy CoulDn't FinD out nEil's motivEs oF killing
B．thEy hAD no iDEA who might BE thE CriminAl
C．thE BoDiEs CoulDn't provE thE killing By nEil
D．thEy CoulD not know whEn nEil lEFt For lonDon